Program

• the implementation of the scrollarea mega-widget;
• commands for user-friendly mouse wheel event handling in scrollable widget containers like BWidget ScrollableFrame and iwidgets::scrolledframe;
• demo scripts illustrating the use of the Scrollutil package in connection with the above-mentioned scrollable widget containers;
• a programmer's manual and reference pages, in HTML format.

The talk shows by means of a series of demo scripts how the scrollutil::scrollarea widget is distinct from all similar widgets, and how to use the mouse wheel event handling provided by the Scrollutil package in BWidget ScrollableFrame widgets.

Key features include:

• Very simple API for a minimal learning curve
• Secure by default
• Cross-platform - works with any web server, or stand-alone
• A single file of Tcl for ease of integration into existing projects

• Creation of oo::class like widgets at C and script level
• Add, delete and modify options at C and script level
• oo::class versions of frame, labelframe and toplevel
• oo::class graph widget (formerly rbc::graph)
• oo::class path widget (formerly tkpath)

Since 1991 I use a little solar panel on my balcony to operate lamps, radio, tablet PC, TV etc. Recently I also started to measure voltage and current and visualize the solar-data collected. Of course I use Tcl for this!

In my talk I want to present the various aspects of Tcl-programming used in this project.
Topics touched are:

• writing an assembler for the Attiny85 in Tcl
• programming this microcontroller with an Raspberry-Pi via SPI-interface
• communicating via I2C-interface with an Raspberry-Pi and other I2C-chips
• using the Dropbox-uploader of Andrea Fabrizi to load and store data via Dropbox-cloud
• visualizing solar-data with Tk and the canvas-widget

During the last years I used Tcl as an everyday tool in a well known and established environment.
After moving to a new company and a new environment I found myself challenged with unexpected obstacles and hurdles in using Tcl. As I felt quickly like a blacksmith robbed of his tools, I looked for new ways to overcome these problems.

My talk should illustrate the usage in new environments.

• A hand scanner which acts as a keyboard input was already available. An application had to be programmed to work with the web based invoicing system as separate module for supporting the invoice creation.
• For stock taking a mobile solution had to be created. An application using smart phones as input devices had to developed to allow a multi user access to the inventory database.
• In shops dealing with ready money the detailed cash flow must be documented on a daily basis using a cash account book. A user interface had been developed which allows the convenient input of the coins and banknotes. Finally a PDF document is created and archived for legal reasons.

I wanted to build a Turing-complete espresso machine whose "coffee recipe" would be in malleable software, instead of hard-wired into the plumbing. Because this was a big break with the history of espresso machines, I knew that a lot of my decisions would be "just plain wrong", as I would have few precedents to follow.

I decided to use Tcl, via Androwish and an included (rooted) Android tablet, to provide the interface to the espresso machine. I hoped that a community of coders and tinkers would form, to create something much better than I could alone.

I’ll talk about the Tcl decisions, what it’s like writing a big app in Androwish, writing a plugin extension mechanism, and bridging to the Internet via Aolserver/Naviserver, REST, Javascript, Amazon and more. Also: a bit about bringing people to Tcl, which for most is their first "freedom to tinker" experience with a home appliance.

Since Tcl 8.6, work is going on to improve Unicode support. For long, Unicode was supposed to be limited to 16 bits, but that's not true any more.
A few TIP's are already finalized for Tcl 8.7 (e.g. TIP #388 and #389), which allow the use of Unicode characters > /uFFFF in Tcl.
Also, there is work done in Androwish (Tcl port for Android), in which full Unicode support is enabled using the -DTCL_UTF_MAX=6 compiler switch.
The disadvantage of this approach is source and binary incompatibility:
All extensions have to be recompiled using the same compiler switch as well, and they have to account for the Tcl_UniChar type not being 16 bits any more.

This presentation will outline a way to overcome this source and binary incompatibility, and lay out a possible path to Tcl9.0, unifying both of those worlds:
Enabling the full Unicode range of characters but - at least - resolve the source compatibility issue as much as possible.

The application for the moment is called DBM (DatabaseManager) and I am planning to open source the software soon.

DBM is basically a to-do list manager, note taken application, etc ... based on tablelist, sqlite, and a few other supplemental packages. It can be used within a group of people working on the same project simultaneously.

The application is a starpack and is serverless (due to sqlite) and does not require anything else to be installed on the computer (zero installation).